The two most widely approaches used by valuators to determine a discount for lack of marketability (DLOM) are restricted stock studies and IPO studies. The restricted stock studies compare transaction prices in restricted shares with contemporaneous trading prices for unrestricted shares. The pre-IPO studies, on the other hand, according to the author, lead to conclusions that are unsound in theory and in practice. In this article, the author discusses six major flaws in the data that, in the author’s opinion, make the pre-IPO studies’ conclusions totally unreliable for determining discounts for lack of marketability. The two most widely approaches used…